Lenses having chromatic effect

ABSTRACT

A lens is provided comprising a substrate, a metal layer comprising a metal material uniformly covering an outer surface of said substrate, a first dielectric layer comprising a first dielectric material uniformly covering said metal layer and a second dielectric layer comprising a second dielectric material gradiently covering only a portion of said first dielectric layer.

FIELD OF THE INVENTION

[0001] The present invention relates to lenses having a dual chromaticeffect when viewed from the side opposed to the wearer.

BACKGROUND OF THE INVENTION

[0002] The present invention relates to lenses, and, in particular, tolenses for use in sunglasses, which are externally treated in such a wayto produce a new dual chromatic effect when viewed from the side opposedto the wearer. In particular, the present invention is directed atlenses that, when viewed from the side opposed to the wearer, reflectlight in two different colors, one of which is reflected in a gradientmanner.

[0003] In the prior art, chromatic effects have been generally achievedon lenses by depositing interference film on the outer surface of thelens. By choosing a film thickness properly, one can get a wide spectrumof reflected colors.

[0004] A common way to obtain a reflected color on the outer surface ofa sunglass lens is to uniformly deposit a stack of dielectric films withalternative high and low refraction indexes. Such lenses are describedin U.S. Pat. No. 3,679,291, which is hereby incorporated by reference.

[0005] Other chromatic lenses and methods for achieving the same aredescribed in U.S. Pat. No. 4,160,584, which is hereby incorporated byreference. In one method, a uniform metallic layer is deposited over asubstrate, and then a uniform dielectric material is deposited over theentire metallic layer. As described in U.S. Pat. No. 4,160,584, bydepositing a thin transparent layer of a dielectric material on a thintransparent layer of metal, the light partially reflected changes itswavelength composition moving from the white light to a colored light ofthe spectrum depending on the thickness of the dielectric layer.

[0006] In a second method, also disclosed in U.S. Pat. No. 4,160,584,the metallic layer is gradiently deposited over the entire substrate andis then uniformly and entirely covered by a dielectric layer. In thiscase the outer surface will appear with a gradient colored reflection atthe top becoming completely clear at the bottom.

[0007] In each of the two methods described above, the resultant lensproduces a single, or single-gradient chromatic effect. That is, whilecolored, each of the lenses are of a single color. Various differentmaterials for use in the metallic and dielectric layers, and thedifferent colors that can be achieved, are described in U.S. Pat. No.5,054,902, which is incorporated herein by reference.

[0008] The present invention is directed at providing a lens having adual chromatic effect by utilizing at least one layer deposited in agradient manner. The present invention is also directed at methods ofmanufacturing such lenses.

SUMMARY OF THE INVENTION

[0009] The present invention is directed to lenses, and, in particular,to lenses for use in sunglasses, treated in such a way to produce a newdual chromatic effect. In particular, the present invention is directedtowards lenses comprising at least one layer deposited in a gradientmanner, such that the lens has at least two zones with differentlycolored reflection. Even more particularly, the present invention isdirected towards lenses comprising at least one layer deposited in agradient manner, such that the lens has at least two zones withdifferently colored reflection, one of which is gradiently reflective.

[0010] In one aspect of the present invention, the lens comprises atleast four layers including a substrate, a first dielectric layercomprising a high index dielectric material uniformly covering an outersurface of the substrate, a second dielectric layer comprising a firstlow index dielectric material uniformly covering the first dielectriclayer, and a third dielectric layer comprising a second low indexdielectric material gradiently covering only a portion of the seconddielectric layer. The first and second low index dielectric materialscan be the same or different materials.

[0011] In a second aspect of the present invention, the lens comprisesat least four layers including a substrate, a metal layer comprising ametal material uniformly covering an outer surface of the substrate, afirst dielectric layer comprising a first dielectric material uniformlycovering the metal layer, and a second dielectric layer comprising asecond dielectric material gradiently covering only a portion of thefirst dielectric layer. The first and second dielectric materials can bethe same or different materials and can be either high or low indexdielectric materials.

[0012] In a third aspect of the present invention, the lens comprises atleast five layers including a substrate, a first metal layer comprisinga first metal material uniformly covering an outer surface of thesubstrate, a first dielectric layer comprising a first dielectricmaterial uniformly covering the first metal layer, a second metal layercomprising a second metal material gradiently covering only a portion ofthe first dielectric layer, and a second dielectric layer comprising asecond dielectric material gradiently covering the second metal layer.The first and second dielectric materials can be the same or differentmaterials and can be either high or low index dielectric materials, andthe first and second metal materials can be the same or differentmaterials.

[0013] In a fourth aspect of the present invention, the lens comprisesat least five layers including a substrate, a first dielectric layercomprising a first dielectric material uniformly covering an outersurface of the substrate, a second dielectric layer comprising a seconddielectric material uniformly covering the first dielectric layer, ametal layer gradiently covering only a portion of the second dielectriclayer and a third dielectric layer comprising a third dielectricmaterial gradiently covering the second metal layer. In a preferredembodiment, the first dielectric material is a high index dielectricmaterial and the second and third dielectric materials can be the sameor different materials and can be either high or low index dielectricmaterials.

[0014] Such lenses provide at least two zones with differently coloredreflection when observed from the side of the lens opposed to the eyesof wearer. In particular, such lenses provide at least two zones withdifferently colored reflection when observed from the side of the lensopposed to the eyes of wearer, one of which is gradiently reflected.

[0015] Other objects and features of the present invention will becomeapparent from the following detailed description, considered inconjunction with the accompanying drawing figures. It is to beunderstood, however, that the drawings are designed solely for thepurpose of illustration and not as a definition of the limits of theinvention, for which reference should be made to the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In the drawing figures, which are not to scale, and which aremerely illustrative, and wherein like reference characters denotesimilar elements throughout the several views:

[0017]FIG. 1 is a cross sectional view of a lens constructed inaccordance with one aspect of the present invention;

[0018]FIG. 2 is a cross sectional view of a lens constructed inaccordance with a second aspect of the present invention;

[0019]FIG. 3 is a cross sectional view of a lens constructed inaccordance with a third aspect of the present invention; and

[0020]FIG. 4 is a cross sectional view of a lens constructed inaccordance with a fourth aspect of the present invention.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

[0021] The present invention relates to lenses externally treated with avacuum deposition technique in such a way to produce a new dualchromatic effect. In particular, the present invention is directedtowards lenses comprising at least one layer deposited in a gradientmanner, which provides a lens having at least two zones with differentlycolored reflection. Even more particularly, the present invention isdirected towards lenses comprising at least one layer deposited in agradient manner, which provides a lens having at least two zones withdifferently colored reflection, one of which is gradiently reflective.

[0022] The present invention is not limited to lenses for use inglasses, or sunglass lenses in particular, but rather the term lens asused herein and in the claims shall be interpreted in its broadest senseto include any type of eye-protecting element or device used to protector shield the eyes of a wearer, such as, for example, lenses, frames,sunglasses, fashion eyewear, sport eyewear, eyeglasses, ophthalmiclenses, visors, shields, face shields, goggles, and the like (as thoseterms are customarily used in the eyewear industry).

[0023] In one aspect of the present invention, as seen in FIG. 1, thelens, generally depicted as 100, comprises four layers including asubstrate 10, a first dielectric layer 20 comprising a high indexdielectric material uniformly covering an outer surface of substrate 10,a second dielectric layer 30 comprising a first low index dielectricmaterial uniformly covering first dielectric layer 20, and a thirddielectric layer 40 comprising a second low index dielectric materialgradiently covering only a portion of second dielectric layer 30. Thefirst and second low index dielectric materials can be the same ordifferent materials.

[0024] In general terms, referring to FIG. 1, a transparent substrate 10is uniformly coated on an outer surface by vacuum deposition with afirst dielectric layer 20. First dielectric layer 20 comprises a highindex dielectric material and is deposited in a constant or uniformthickness over an outer surface of substrate 10. Second dielectric layer30 is then uniformly applied by vacuum deposition on the entire outersurface of first dielectric layer 20. Second dielectric layer 30comprises a low index dielectric material and is deposited in a constantor uniform thickness over the entire outer surface of first dielectriclayer 20. Third dielectric layer 40 is then deposited in a gradientmanner over a portion of the outer surface of second dielectric layer30. Third dielectric layer 40 comprises a low index dielectric materialand, in a preferred embodiment, is deposited in a gradient manner so asto be thicker at the top of lens 100 than at the bottom of lens 100. Asone of skill in the art will recognize after reading and understandingthe present invention, such a lens provides a dual chromatic effect whenviewed from the side opposed to the eyes of a wearer, and, inparticular, provides for a lens having two zones with differentlycolored reflection, one of which is gradient in nature.

[0025] In a second aspect of the present invention, as seen in FIG. 2,the lens, generally depicted as 200, comprises at least four layersincluding a substrate 15, a metal layer 25 comprising a metal materialuniformly covering an outer surface of substrate 15, a first dielectriclayer 35 comprising a first dielectric material uniformly covering metallayer 25, and a second dielectric layer 45 comprising a seconddielectric material gradiently covering only a portion of firstdielectric layer 35. The first and second dielectric materials can bethe same or different materials and can be either high or low indexdielectric materials.

[0026] In general terms, referring to FIG. 2, a transparent substrate 15is uniformly coated on an outer surface by vacuum deposition with ametal layer 25. Metal layer 25 comprises a metal material and isdeposited in a constant or uniform thickness over an outer surface ofsubstrate 15. First dielectric layer 35 is then uniformly applied byvacuum deposition on the entire outer surface of metal layer 25. Firstdielectric layer 35 comprises a high or low index dielectric materialand is deposited in a constant or uniform thickness over the entireouter surface of metal layer 25. Second dielectric layer 45 is thendeposited in a gradient manner over a portion of the outer surface offirst dielectric layer 35. Second dielectric layer 45 comprises a highor low index dielectric material and, in a preferred embodiment, isdeposited in a gradient manner so as to be thicker at the top of lens200 than at the bottom of lens 200. As one of skill in the art willrecognize after reading and understanding the present invention, such alens provides a dual chromatic effect when viewed from the side opposedto the eyes of a wearer, and, in particular, provides for a lens havingtwo zones with differently colored reflection, one of which is gradientin nature.

[0027] Specifically, with regard to FIG. 2, layers 25 and 35 lower thetotal transmission of the substrate by about 25%. For example, if a 20%transmission sunglass lens is treated one can obtain a violet reflectinglens with a final transmission of 15%. The transmission drop is due tothe metallic layer and the change of reflection color is due to thedielectric layer. The final result is that, looking at the externalsurface of the lens 200, at the top the previous violet reflectionshifts into blue leaving the original violet at the bottom. However,looking through the lens internally, the transmission is maintaineduniformly because the added dielectric layer 45 does not change thetransmission of lens 200.

[0028] In a third aspect of the present invention, as seen in FIG. 3,the lens, generally depicted as 300, comprises at least five layersincluding a substrate 50, a first metal layer 60 comprising a firstmetal material uniformly covering an outer surface of substrate 50, afirst dielectric layer 70 comprising a first dielectric materialuniformly covering first metal layer 60, a second metal layer 80comprising a second metal material gradiently covering only a portion offirst dielectric layer 70, and a second dielectric layer 90 comprising asecond dielectric material gradiently covering second metal layer 80.The first and second dielectric materials can be the same or differentmaterials and can be either high or low index dielectric materials, andthe first and second metal materials can be the same or differentmaterials.

[0029] In general terms, referring to FIG. 3, a transparent substrate 50is uniformly coated on an outer surface by vacuum deposition with afirst metal layer 60. Metal layer 60 comprises a first metal materialand is deposited in a constant or uniform thickness over an outersurface of substrate 50. First dielectric layer 70 is then uniformlyapplied by vacuum deposition on the entire outer surface of metal layer60. First dielectric layer 70 comprises a high or low index dielectricmaterial and is deposited in a constant or uniform thickness over theentire outer surface of metal layer 60. Second metal layer 80 is thendeposited in a gradient manner over a portion of the outer surface offirst dielectric layer 70. Second metal layer 80 comprises a secondmetal material and, in a preferred embodiment, is deposited in agradient manner so as to be thicker at the top of lens 300 than at thebottom of lens 300. Second dielectric layer 90 is then deposited in agradient manner over an entire outer surface of second metal layer 80.Second dielectric layer 90 comprises a high or low index dielectricmaterial and, in a preferred embodiment, is deposited in a gradientmanner so as to be thicker at the top of lens 300 (and at the top ofsecond metal layer 80) than at the bottom of lens 300 (and at the bottomof second metal layer 80). As one of skill in the art will recognizeafter reading and understanding the present invention, such a lensprovides a dual chromatic effect when viewed from the side opposed tothe eyes of a wearer, and, in particular, provides for a lens having twozones with differently colored reflection, one of which is gradient innature.

[0030] In a fourth aspect of the present invention, as seen in FIG. 4,the lens, generally depicted as 400, comprises at least five layersincluding a substrate 55, a first dielectric layer 65 comprising a firstdielectric material uniformly covering an outer surface of substrate 55,a second dielectric layer 75 comprising a second dielectric materialuniformly covering first dielectric layer 65, a first metal layer 85comprising a metal material gradiently covering only a portion of seconddielectric layer 75, and a third dielectric layer 95 comprising a thirddielectric material gradiently covering metal layer 85. In a preferredembodiment the first dielectric material is a high index dielectricmaterial and the second and third dielectric materials can be the sameor different materials and can be either high or low index dielectricmaterials.

[0031] In general terms, referring to FIG. 4, a transparent substrate 55is uniformly coated on an outer surface by vacuum deposition with afirst dielectric layer 65. First dielectric layer 65 comprises a firstdielectric material and is deposited in a constant or uniform thicknessover an outer surface of substrate 55. In a preferred embodiment, firstdielectric material is a high index dielectric material. Seconddielectric layer 75 is then uniformly applied by vacuum deposition onthe entire outer surface of first dielectric layer 65. Second dielectriclayer 75 comprises a high or low index dielectric material and isdeposited in a constant or uniform thickness over the entire outersurface of first dielectric layer 65. Metal layer 85 is then depositedin a gradient manner over a portion of the outer surface of seconddielectric layer 75. Metal layer 85 comprises a metal material and, in apreferred embodiment, is deposited in a gradient manner so as to bethicker at the top of lens 400 than at the bottom of lens 400. Thirddielectric layer 95 is then deposited in a gradient manner over anentire outer surface of metal layer 85. Third dielectric layer 95comprises a high or low index dielectric material and, in a preferredembodiment, is deposited in a gradient manner so as to be thicker at thetop of lens 400 (and at the top of metal layer 85) than at the bottom oflens 400 (and at the bottom of metal layer 85). As one of skill in theart will recognize after reading and understanding the presentinvention, such a lens provides a dual chromatic effect when viewed fromthe side opposed to the eyes of a wearer, and, in particular, providesfor a lens having two zones with differently colored reflection, one ofwhich is gradient in nature.

[0032] With regard to substrates 10, 15, 50 and 55, the preferredmaterial is any optical material for lenses, including but not limitedto glass, plastic, CR39, polyamides, polycarbonate, polymethylmethacrylate, polyurethane, cellulosic polymers, and substrates of thesame materials but incorporating a polarizing film into the body of thesubstrate or adherent to its surface. The thickness of the substrate isnot critical to the operation of the lens, but is merely a matter ofdesign choice to one of skill in the art. By way of a non-limitingexample, if the substrate is CR-39, then substrate 10 can be 1 to 4 mmthick, and is preferably 1.4 mm to 3 mm thick, and most preferably is 2mm thick.

[0033] With regard to metal layers 25, 60, 65, 80 and 85, any metalliclight absorbing material commonly used in the field can be used as themetallic material including, but not limited to, silver, chromium,aluminum, gold, nickel, germanium and the like. In fact, all the metalscited into the CERAC catalog of evaporation materials are suitable foruse as the metallic material in the metal layers of the presentinvention. The materials used in any of the metal layers can be the sameor different materials than those used in any other metal layer of thesame lens. Chromium and aluminum are the presently preferred materialsfor use in the metal layers. The thickness of metal layers is notcritical to the operation of the present invention, but rather the metallayers can be deposited at a thickness sufficiently thin so as to betransparent. By way of a non-limiting example, if chromium is used asthe metallic material then the thickness of the metal layers depositedon the substrate surface can range from 50 to 300 angstroms.

[0034] With regard to the materials of the dielectric layers 20, 30, 35,40, 45, 65, 70, 75, 90 and 95, each of these materials can be the sameor different materials. The preferred dielectric materials are generallySiO or SiO₂, but other dielectric materials can be used, including, butnot limited to, TiO₂, Cr₂O₃ and the like. The preferred low indexdielectric materials are SiO or SiO₂ and the preferred high indexdielectric material is Cr₂O₃. The thickness of the uniformly applieddielectric layers 30, 35, 65, 70 and 75, is not critical to theoperation of the present invention, but rather is a function of thedesired color of the reflection to be achieved. For example, byincreasing the deposition thickness of SiO on a mirror-coated CR39substrate, one can obtain at first a gold reflection, then a brownishreflection, then a violet reflection, and then a blue reflection, allwithout changing the transmission of the lens. By way of non-limitingexamples, the following identifies the relationship between thickness ofSiO layer deposited and reflection color obtained: 300 angstrom Yellow550 angstrom Violet 750 angstrom Blue

[0035] Deposition of SiO₂ is similar but the reflection colors aresomewhat weaker.

[0036] With regard to gradiently applied dielectric layers 40, 45, 90and 95, the principle is the same as detailed above with respect to theuniformly applied dielectric layers. By way of a non-limiting example,with regard to FIG. 2, one can deposit a first dielectric layer 35 ofSiO at a thickness to obtain a violet color reflection. The lower partof the lens can then be masked, and the deposition of SiO continues toform second dielectric layer 45 on the upper part of the lens, therebyachieving a blue reflection on the upper part of the lens that includessecond dielectric layer 45 while maintaining the violet color on thelower part of the lens which does not include second dielectric layer45.

[0037] With regard to the materials of high index dielectric layers 20and 65, the preferred high index dielectric material is Cr₂O₃, but, asone of skill in the art will recognize after considering the presentinvention, other high index dielectric materials can be used as a matterof design choice without departing from the spirit of the invention. Thethickness of the uniformly applied high index dielectric layers 20 and65 are not critical to the operation of the present invention, butrather are a function of the desired color of the reflection to beachieved.

[0038] As one of skill in the art will recognize, additional layers canbe added to the lenses of the present invention without departing fromthe spirit of the invention. Further, while FIGS. 1 through 4 of thepresent invention depict the gradient layers ending approximately halfway down the lens, the exact starting and ending points of the gradientlayers is not critical to the operation of the present invention, and ismerely shown as starting at the top and ending half way down forillustrative purposes only. Such gradient layers could also extend froma side-to-side fashion on the lens.

[0039] As one of skill in the art will recognize, the present inventionprovide lenses with at least two zones with differently coloredreflection if one observes the lens from the side opposed to the eyes ofwearer, while at the same time providing a lens which is uniformlytransparent if observed from the wearer even if the mirror coated sidehas two differently tinted reflection areas. The present invention alsoprovides a lens with a gradient mirrored zone on another coloredmirrored area.

[0040] Thus, while there have been shown and described and pointed outnovel features of the present invention as applied to preferredembodiments thereof, it will be understood that various omissions andsubstitutions and changes in the form and details of the disclosedinvention may be made by those skilled in the art without departing fromthe spirit of the invention. It is the intention, therefore, to belimited only as indicated by the scope of the claims appended hereto.

[0041] It is also to be understood that the following claims areintended to cover all of the generic and specific features of theinvention herein described and all statements of the scope of theinvention which, as a matter of language, might be said to fall therebetween. In particular, this invention should not be construed as beinglimited to the dimensions, proportions or arrangements disclosed herein.

1-9. (Canceled)
 10. A lens comprising: a substrate; a metal layer comprising a metal material uniformly covering an outer surface of said substrate; a first dielectric layer comprising a first dielectric material uniformly covering said metal layer; and a second dielectric layer comprising a second dielectric material gradiently covering only a portion of said first dielectric layer.
 11. The lens according to claim 10, wherein said first dielectric material and said second dielectric material are the same material.
 12. The lens according to claim 10, wherein said first low index dielectric material and said second low index dielectric material are different materials.
 13. The lens according to claim 10, wherein said second dielectric layer covers approximately one half of said first dielectric layer.
 14. The lens according to claim 10, wherein second dielectric layer covers approximately a top half of said first dielectric layer when said lens is in its normal operating orientation.
 15. The lens according to claim 10, wherein said metal material comprises an element selected from the group consisting of silver, chromium, aluminum, gold, nickel and germanium.
 16. The lens according to claim 10, wherein said first dielectric material comprises a material selected from the group consisting of SiO, SiO₂, TiO₂, and Cr₂O₃.
 17. The lens according to claim 10, wherein said second dielectric material comprises a material selected from the group consisting of SiO, SiO₂, TiO₂, and Cr₂O₃.
 18. The lens according to claim 10, wherein said substrate is a material selected from the group of glass, plastic, CR39, polyamides, polycarbonate, polymethyl methacrylate, polyurethane, cellulosic polymers, and substrates of the same materials but incorporating a polarizing film into the body of the substrate or adherent to its surface.
 19. The lens according to claim 10, wherein said lens is a sunglass lens for use in a pair of sunglasses. 20-36. (Canceled)
 37. A method of manufacturing a lens having a chromatic effect comprising the steps of: providing a substrate having an outer surface; vacuum depositing a metal layer at a uniform thickness over said outer surface of said substrate; vacuum depositing a first dielectric layer at a uniform thickness over an entire outer surface of said metal layer; masking a portion of an outer surface of said first dielectric layer; and vacuum depositing a second dielectric layer at a gradient thickness over an unmasked portion of said first dielectric layer. 38-39. (Canceled) 